Promise
by sebacielfantasies
Summary: Levi reluctantly makes a promise that he hopes he'll be able to keep. Three-shot kind of thing. Major character death, as a warning. I don't own AOT/SNK.
1. Chapter 1

It's a normal day when Levi makes a promise he won't be able to keep.

He's in his bed, with his back against the headboard and one leg crossed over the over. The bed dips up and down as Eren moves excitedly in it. Too much excitement, if you ask him.

"Hey, brat," he says, stifing the urge to lean over and strangle the teen, "would you quit it? Keep moving like that and you'll break the bed."

Eren, with effort, goes still and resorts to tapping his fingers on his knee. "Sorry, Levi."

"What has you so excited, anyway? It's unsettling."

"Ah, well, um . . ." Eren scratches at his neck. "It's silly, really."

"Everything you say is silly; I'm used to it," he points out. His eyebrows raise, and his mild curiousity nudges him toward the boy. "Out with it."

"I just can't stop thinking about the sea," Eren blurts out, and even his voice rises with the excitement bubbling up. He wrings his hands, over and over, as if to channel his nerves to his fingertips. "Me and Armin were talking about it today, and I was just thinking that maybe the chances are better now. To go see it, I mean."

Levi has to swallow down a laugh. His eyes meet Eren's, and he is astonished to see how serious they are. "You think your chances are better? You must have your eyes closed, then, if you think that."

One look at Eren's wide, blue-green eyes, however, proves otherwise. He isn't one to avoid to truth with a look the other way or a closing of the eyelids. He looks on, painfully and angrily, as his friends or family die. (If he can't save them, that is.) He then wields that raw emotion into a weapon, and that's what intrigues Levi so.

"The chances really are better, though!" says Eren. "Ever since joining the Survey Corps, it wasn't just some unreachable dream I had as a kid. It's real now, something that's actually possible, even if the chances aren't that big, you know?"

Levi doesn't know. He has no particular dream in mind, never has. He hasn't thought much about the aftermath once they defeat the Titans.

"Don't you have some kind of dream? Something you want to do once we kill all the Titans?"

Eren's words are an echo of his own thoughts, much to his irritation. Is the kid a fucking mind reader or something? He gives a halfhearted shrug. "I don't have any dream, Eren, I'm not five. I have a goal, and that is to annihilate the Titans and restore humanity. That's it."

"Come on, Levi, that can't be all!" Eren crawls closer to him, mouth fixed in a pout. "I want that too, obviously . . . But isn't there something else?"

He shakes his head; no, there isn't and there doesn't have to be. His glare sharpens, daring Eren to continue his pestering. Eren shrivels back a little, but then he smiles.

"You can have my dream, then! Wouldn't you want to see the sea? Me and Armin read about it, and it's supposed to be amazing, with these huge killer waves and . . ." His words pour out like spilled tea, jumbles of words pooling on the floorboards before Levi can process them.

As much as Levi wants to sit there and simply listen to Eren's bright voice, he doesn't want him to get the wrong idea, so he interrupts the boy with a kiss. Eren makes a noise of surprise despite the fact that this is nothing new.

"L-Levi!" says Eren once the man pulls away. He licks his lips, a blush like fire on his cheeks. "Someone could see, you know! The door is wide open!"

Ignoring Eren's spluttering completely, he says, "I don't want to steal your dream, brat. Are you stupid?"

"Not steal," Eren says. "We'd be sharing it." Levi opens his mouth, another protest on his tongue, but Eren continues, "I want to see it, Levi. I want to see it with Armin, and Mikasa . . . And I want to see it with you, too."

"You don't need me there. I'm not even interested in it; I'll just ruin your mood."

"No, you won't." Eren's eyes are bright and insistent. "As long as you're there, I'll be happy."

The roof of Levi's mouth dries up. He looks away with a scoff. But his heart is beating the way it would if he were in danger, fast and frenzied. Except he isn't in danger, so this has to be for a different reason entirely.

It is true that he doesn't care about the sea. He sees water every day, after all; why would he want to see more of it? It makes no sense.

But, to his surprise, the realization that Eren wants to see it with _him_ makes his throat constrict with something that feels like gratitude.

"You're pretty desperate to have me go with you, aren't you?" he teases, earning another blush from Eren. "I'm willing to believe you're just scared to venture out there alone, defenseless and vulnerable."

"E-Eh?" Eren waves his arms about and shakes his head. "That's not it! I can handle whatever comes at me by myself! I don't need some midget corporal to protect me . . . And, um, if for some reason I couldn't handle it, Mikasa would be with me too, so . . ."

"You've got one foot in the grave, Eren," Levi warns. "No, on second thought, your whole fucking leg. I better not have heard what I thought I just did."

"What?" Eren frowns, but then his face lights up with understanding. Soon followed by terror. "Ah, I'm sorry, it just came out . . . I couldn't help it."

Levi's hands seize his waist, and the boy yelps. He wriggles and twists, but the grip is strong as steel.

"Wait, please don't kill me! I'm sorry!"

"I've always wondered," the corporal says, pulling him over, "whether or not you're ticklish. This is the perfect opportunity to find out, I think."

Eyes widening with realization, he struggles further, to no avail. "Levi, wait!" Hands cup Eren's chin, fingers tickling the sensitive skin, and he lets out an adorable squeak. "S-Stop it!"

Levi's fingers venture under the boy's shirt, dancing on his stomach and sides. Eren bursts into giggles, and it makes the corporal's own lips spread into a small smile. Eren's limbs fly about, out of his control, and the blankets are kicked off the bed.

"This - is very - immature -" gasps Eren, but Levi is having far too much fun with this to care. He tickles him until his face is red and his eyes are watering from laughing.

When he withdraws, finally halting his attacks, Eren sits up. His breaths come out ragged, and it is a while before he speaks.

"I . . . hate you," he says, his brows scrunching up as he glares.

"If you hated me, you wouldn't have forced me to go find some sea with you." Levi has to stop himself from smiling a little at Eren's angry face. It looks adorable, like an angry kitten with no claws.

"Oh, that's right!" Just like that, his anger is gone, evaporated like chimney smoke. He grins. "Does that mean you'll come with us? Please?"

The hopeful look in Eren's eyes, the easy smile he wears- it all makes Levi's heart ache. It makes the decision one of the easiest he's ever made. "Yes, I will."

Eren's smile widens, as if to make up for Levi's lack of one. Levi has begun to love that smile. "Really? Promise?"

At that, though, he frowns, and the muscles in his jaw tighten. "No, I can't promise-"

Eren's expression crumples like a house of cards. "Why not?"

Levi sighs; is it not obvious?

"Do I have to spell it out for you? One of us might die before this ends, Eren. And I can't guarantee that-"

"I know that!" interrupts Eren, and Levi has to restrain from punching him for interrupting him again. "Okay, how about this: if I die, will you still go and see it? And take Armin and Mikasa too? I really know you'll love it, Levi, and I-"

It's his turn to interrupt, now. "No," Levi says sharply, "don't you dare. You'll make it out. You'll survive because that's what you do. So don't go talking about dying and leaving me with this shit, understand? Go look at the sea yourself."

"But you just said-"

"I didn't mean that you might die. I won't allow that. You're my responsibility."

Levi states it calmly, as if it's just a universally accepted truth, like how the dirt is brown and the grass green. Not a trace of hesitation. He would protect Eren to his last breath, and that is that.

"Okay," Eren says slowly, startled. His back straightens up. "If you can guarantee that I will still alive, then why can't you promise?" His gaze hardens; he must have seen the answer in Levi's eyes. "And if you're going to say you might die, you won't. I . . . I know that I might not be as strong as you or as experienced, but I won't let you die, either. Never."

Eren's voice is powerful, confident. Levi's eye twitches.

"I said I'd kill all the Titans," says Eren, and his eyes are murderous; they would frighten anyone who didn't know him. "And if I see one coming towards you, I'll kill it. So- So you don't have to worry about it, Levi."

Levi is rarely fazed by what goes on around him, but now he is at a loss as to what to feel. No one promises to have his back these days- not when he's Humanity's Strongest. He's supposed to do the protecting, isn't he? What else is he good for? Cleaning?

"That's nice, Eren, but I can take care of myself. I don't need you to protect me." He tugs Eren over again, but this time not to torment him. Instead he buries his face into the boy's shoulder, inhaling his scent. "Let me protect you."

"If you can take care of yourself, you have confidence that you'll survive," says Eren, quietly. His arms wrap around Levi's shoulder blades, and the contact is nice. "So promise. Promise me that you'll live, and that we'll both go find the sea together."

Levi's trapped. He told Eren that he won't let him die, under any circumstances- he also said he himself would survive, and that he doesn't need protection. As a leader, he is not supposed to go back on his word, either.

"I promise," he says finally. "We'll go find the sea together."

Eren gives a victory shout, and his arms wrap tighter around Levi's frame. The warmth oozing from him is soothing, and the happiness in his voice as he depicts the saltwater sea once more melts Levi's uneasiness. Some of it, at least.

Levi's dream isn't seeing the sea, he decides. It never will be, regardless of Eren's influencing. That is Eren and his friends' foolish dream, not his.

But perhaps his dream is Eren himself.


	2. Chapter 2

Weeks later, it's during the end of the expedition that things goes wrong.

The beginning of the expedition started like any other. Everyone got in formation, a plan of retreat was designed in the happenings of something going badly—everything was in place.

Eren's with Levi, obviously, as the little Titan shifter is entirely his responsibility. He rides beside him as they venture farther and farther from their base. There's nothing but dusty terrain around them save for a distant forest, which is dangerous, for they have no way to use their 3DMGs. They're like sitting ducks out here.

Levi always had a good sense of intuition. So when his stomach clenches and a feeling of unease creeps up his skin, he knows something's wrong.

His suspicions are confirmed when the Titans lumber out of the woods to their left.

Levi's jaw tightens; didn't seem like they were in luck today. He wonders why the left flank didn't shoot a signal flare as a warning. Then he reasons they might have died before they got the chance.

Instantly, his body tensed and ready for a fight, he looks behind him and shouts orders to the soldiers gathered. They all have no choice but to fight now. They've already been spotted, after all.

Collective murmurs and gasps spread throughout the group like a virus—but Levi isn't listening, he's examining the enemy. There's quite a few of them, all of different shapes and sizes. They're about 100 meters away and making good time; they'll be here within minutes.

His hands find their blades, and he slides them out.

Eren makes a noise to his right, and Levi looks over to see narrowed blue-green eyes. "We're at a disadvantage," growls Eren. "There's no way to use the mobility gear. I need to—"

"Don't shift, Eren." Levi's voice is firm. "We have it under control. If you shift, you may lose control and kill every one of us. Do you want that?"

The boy's expression changes to one of conflict, and he shakes his head so hard his hood slips off. "No, but—"

"You will listen to me, as your commanding officer," says Levi. He's off his horse now, eyes trained on the nearing Titans. "Get yourself somewhere safe, we'll handle this."

"But—"

"Now, Eren." He whirls on the boy, grabs his collar, and tugs him down to eye-level. "You shifting is too unpredictable, we will only use that if it's absolutely necessary. Now, please, _get yourself safe."_

Eren hesitates, again. Why does he have to be so goddamn stubborn? "I won't! I have blades, too—I don't have to shift, I'll still fight—"

He's being too selfish, Levi realizes, and grits his teeth. He's never acted this way before, and it makes him sick. But he doesn't want Eren to fight; he wants to keep him safe and happy and _breathing._

But Eren is a soldier, and fighting is what he lives for. He has the weapons, he has the potential, he has the bravery. There's no reason he shouldn't be allowed to fight.

"Fine," Levi sighs, and he tugs Eren the rest of the way, joining their lips. Other soldiers might notice, but Levi can't find it in himself to care. "Just don't die, alright? If you do, I'll go find your ghost and kill you again. Are we clear?"

"Roger!" says Eren, and he pulls away with a determined smile. "Same to you, Corporal Levi. Remember, you have a promise to keep."

Levi nods; he glances back at the enemy and knows they are out of time. "I do. We'll find the sea together, brat."

With that, they part ways, and the fight begins.

The fight doesn't last long. The Titans come upon them, towering above the humans like their very own walls. The soldiers' blades slide out, shiny and sharp. 3DMGs activate, and their hooks have nothing to sink into but the enemies themselves, so into the Titans' flesh they go.

Levi's hands—his entire body—is moving out of instinct. He hardly has to concentrate as he flies in the air, slicing and stabbing and piercing. His blades are like an extension of his limbs as they maneuver through warm Titan flesh.

He lands on one Titan's shoulder, and slices his neck before the Titan can even notice the flea he has gotten. While Levi is there, in the split second before he jumps to the next beast, he glances around. A relieved sigh escapes his lips when he sees Eren, his blades raised and his mouth open in a snarl. He almost looks like an avenging angel, Levi thinks with amusement.

Levi's not too bad himself. He's a killing machine. Titans fall before him like dominos, then fizzle away into a fiery smoke, filling up the air above.

Some time later, as he is finishing off one the last Titans, he realizes just how much the smoke has accumulated. It blocks his vision like a morning fog, which is irritating, because now he can no longer look out for the brat.

He makes his way past the wreckage of evaporating bodies, and finds a safe area. Screams pound into his eardrums, agonized cries—something Levi was able to ignore as he fought. Now, though, in the silence between one fight and the next, he can hear everything.

His eyes pick through the soldiers, some holding their own and some not. One man is trapped in a Titan's jaw—then, with a loud _crunch_ , only his upper body is stuck between the monster's teeth. The sight reminds Levi that he needs to leap back into action, before too many of his men are killed.

But he has to find Eren first.

Normally Levi wouldn't stop right in the middle of a battle, but now he can't help it; his heart feels odd and his stomach feels nauseous. One glance is all he needs. One flash of the teen, with his angry foolish eyes and his shit-eating grin.

He doesn't find him.

Perhaps Levi's too wired up? Forcing himself to calm the fuck down, he looks again, and the results are anything but satisfying.

The gaseous Titan smoke is funneling into his ears and cutting off airflow. His brain is numb, he can't think, he can't breathe—

"Eren!" he calls out, and he whirls around, frantic. "Eren!"

There all soldiers, all around him. None are Eren.

His eyes dart to the few Titans that aren't dead—most have been killed now, by him and his men—there are no humans caught in their mouths, no screaming Eren is in sight.

Fuck, his hands are shaking, his mouth is as dry as paper; this can't be happening. _No._

But as long as there is no body, there is still a chance. Eren may be out there, injured. Or maybe he chose to follow Levi's advice and go somewhere safe.

Somehow he doubts this. The rational part of his brain is kicking in, telling him that a missing person is a dead person. A missing person that has, most likely, become a Titan's lunch.

Levi curses, then begins to trek through the carnage anyway, eyes on the prowl for something, anything. He calls out Eren's name like a broken record, and his voices catches around it, breaking and cracking.

"Eren!" he yells, and he hates how weak he sounds. "Eren, don't you dare be fucking dead! Don't you _dare._ I'm not breaking my promise, you hear?"

He calls out for Eren a few more times, a hopelessly pointless action, before a hand clamps down on his shoulder. Heart seizing, Levi whirls around, and the hope he feels is tangible, precious. "Eren?"

It's not Eren, it's a soldier. The soldier looks apologetically at him, then clears his throat. "S-Sir, we think we should retreat . . . We can't possibly kill all those Titans."

"All those Titans? What is that supposed to mean . . . ?" The soldier points, and Levi turns around, seeing something he had somehow missed before. More Titans have come out of the forests—much too many to handle with so few men. He frowns. _How did I not notice this until now?_

The soldier is right. Retreat is the best option. Yet Levi shakes his head. "No, we can't. The brat—Jaeger—he's still out here somewhere, I need to find him—"

"He's probably dead, Captain," the man says, and Levi has to stop from killing him at this point. _No,_ he wants to say, _that's not fucking possible._ "Are you really going to risk all your men for one little twerp? It's not worth it."

The man's right, but Levi doesn't want to believe it. It's ridiculous to risk all their men for one little brat that's probably already dead.

"I promised him," he mumbles. "I promised we'd find the sea . . ."

"Uh, Captain? We need to go, now—"

The soldier, in a foolishly brave gesture, shakes the corporal's shoulders, hard. But it's what Levi needs. He still feels like he's sinking, but the shake gives him a breath of much needed air. His stiff spine straightens, and he inhales, sharply and deeply. His mind clears. His surroundings flood back into focus.

The Titans are almost upon them, Levi notes after a quick glance. A glance at his men and he knows it would be suicide to stay here. Of the soldiers that survived, only a mere few are standing and seemingly uninjured. The rest are in scattered heaps among the field, some cradling broken legs, others missing limbs altogether. Pained faces look to his own, and he knows they are awaiting orders.

If they don't retreat now, there is a high possibility that everyone, including himself, will die. But if they do, he'll be leaving his charge behind. He'll be breaking his promise.

It's one of the hardest decisions of his life.

He retreats.


End file.
